x86/boot/e820: Use 'enum e820_type' in 'struct e820_entry'

Use a stricter type for struct e820_entry. Add a build-time check to make
sure the compiler won't ever pack the enum into a field smaller than
'int'.

No change in functionality.

Cc: Alex Thorlton <athorlton@sgi.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Huang, Ying <ying.huang@intel.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul Jackson <pj@sgi.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Tejun Heo <tj@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

diff --git a/arch/x86/include/asm/e820/types.h b/arch/x86/include/asm/e820/types.h
index 1c342682553544c59f11c5676f58e4a4f56bd8ef..eb313b62d548fc42dba59ed2e274372f17d3781b 100644 (file)
--- a/arch/x86/include/asm/e820/types.h
+++ b/arch/x86/include/asm/e820/types.h
@@ -1,37 +1,6 @@
 #ifndef _ASM_E820_TYPES_H
 #define _ASM_E820_TYPES_H
 
-enum e820_type {
-       E820_RAM                = 1,
-       E820_RESERVED           = 2,
-       E820_ACPI               = 3,
-       E820_NVS                = 4,
-       E820_UNUSABLE           = 5,
-       E820_PMEM               = 7,
-
-       /*
-        * This is a non-standardized way to represent ADR or
-        * NVDIMM regions that persist over a reboot.
-        *
-        * The kernel will ignore their special capabilities
-        * unless the CONFIG_X86_PMEM_LEGACY=y option is set.
-        *
-        * ( Note that older platforms also used 6 for the same
-        *   type of memory, but newer versions switched to 12 as
-        *   6 was assigned differently. Some time they will learn... )
-        */
-       E820_PRAM               = 12,
-
-       /*
-        * Reserved RAM used by the kernel itself if
-        * CONFIG_INTEL_TXT=y is enabled, memory of this type
-        * will be included in the S3 integrity calculation
-        * and so should not include any memory that the BIOS
-        * might alter over the S3 transition:
-        */
-       E820_RESERVED_KERN      = 128,
-};
-
 #include <uapi/asm/e820/types.h>
 
 /*

diff --git a/arch/x86/include/uapi/asm/e820/types.h b/arch/x86/include/uapi/asm/e820/types.h
index 54b812e80bac119c8100da4abbc3f85d73193482..65c7a1beab224b88975b2ad42dd2b41532b55f42 100644 (file)
--- a/arch/x86/include/uapi/asm/e820/types.h
+++ b/arch/x86/include/uapi/asm/e820/types.h
@@ -6,14 +6,45 @@
 
 #ifndef __ASSEMBLY__
 
+enum e820_type {
+       E820_RAM                = 1,
+       E820_RESERVED           = 2,
+       E820_ACPI               = 3,
+       E820_NVS                = 4,
+       E820_UNUSABLE           = 5,
+       E820_PMEM               = 7,
+
+       /*
+        * This is a non-standardized way to represent ADR or
+        * NVDIMM regions that persist over a reboot.
+        *
+        * The kernel will ignore their special capabilities
+        * unless the CONFIG_X86_PMEM_LEGACY=y option is set.
+        *
+        * ( Note that older platforms also used 6 for the same
+        *   type of memory, but newer versions switched to 12 as
+        *   6 was assigned differently. Some time they will learn... )
+        */
+       E820_PRAM               = 12,
+
+       /*
+        * Reserved RAM used by the kernel itself if
+        * CONFIG_INTEL_TXT=y is enabled, memory of this type
+        * will be included in the S3 integrity calculation
+        * and so should not include any memory that the BIOS
+        * might alter over the S3 transition:
+        */
+       E820_RESERVED_KERN      = 128,
+};
+
 /*
  * A single E820 map entry, describing a memory range of [addr...addr+size-1],
  * of 'type' memory type:
  */
 struct e820_entry {
-       __u64 addr;
-       __u64 size;
-       __u32 type;
+       __u64                   addr;
+       __u64                   size;
+       enum e820_type          type;
 } __attribute__((packed));
 
 #endif /* __ASSEMBLY__ */

diff --git a/arch/x86/kernel/e820.c b/arch/x86/kernel/e820.c
index 511402d88795f494c62d0cbe141b43c63fccf22a..010a289ddd9f47f17cb0d89502ad4ffb8db8baba 100644 (file)
--- a/arch/x86/kernel/e820.c
+++ b/arch/x86/kernel/e820.c
@@ -1164,6 +1164,9 @@ void __init e820__memory_setup(void)
 {
        char *who;
 
+       /* This is a firmware interface ABI - make sure we don't break it: */
+       BUILD_BUG_ON(sizeof(struct e820_entry) != 20);
+
        who = x86_init.resources.memory_setup();
 
        memcpy(e820_table_firmware, e820_table, sizeof(struct e820_table));